JPH0671224B2 - iD code collection method - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to an iD code collecting method for collecting an identification (iD) code unique to a moving body moving in a predetermined area.

[Conventional technology]

In this type of system, it is general that the iD code unique to each individual is transmitted only when a calling signal is received from the center device, instead of constantly outputting the iD code unique to the mobile unit. Therefore, the center device constantly outputs a calling signal toward a certain (limited) area, and when a moving body moving into this area receives the calling signal, its own iD Since it will output the code,
The center device receives the transmitted iD code.

[Problems to be solved by the invention]

In the system as described above, it is premised that only one individual returning the iD code exists within the range where the center device outputs the calling signal. That is, when there are two or more individuals, the center device cannot receive correct data because two or more individuals respond to the request at the same time, and thus the iD code cannot be collected. There is a problem of disappearing.

There is no effective method to solve this problem so far, and there is a countermeasure such that only one individual can exist in a predetermined area, such as a passage or a gate where two or more individuals cannot exist. Methods such as preparing objects and sharpening the directivity of the calling signal to narrow the area to be detected are used. However, although such a method can be applied to a large moving body relatively easily, it is not suitable for a small moving body, and therefore there is no suitable method for a small moving body at present. .

The present invention has been made in view of the above point, and the iD code can be separated from each other from a plurality of moving bodies existing in a predetermined area without providing any special means for restricting the position of the moving body. The purpose is to do so.

[Means for solving problems]

The center device is provided with a transmitting means for transmitting a calling signal, and controls the sending of the calling signal by gradually increasing the amplitude with the passage of time, while the mobile side returns the iD code signal to the center side device. Each time, the responder is controlled so as not to send the iD code signal again until a predetermined number of times or a predetermined number of calls is reached. Further, when it is a problem that the response sensitivity changes depending on the angle between the transmitting means and the transponder, a plurality of transmitting means are provided so as to transmit the calling signals in different directions, and each of the calling means is called. The signals are transmitted to each other by a predetermined time in a time division manner.

[Action]

An antenna for transmitting a calling signal for requesting an iD code is arranged in a predetermined area, and the iD code is read from each individual within a certain range formed by this antenna. The ringing signal gradually changes its output power from the antenna from small to large, and sequentially changes from a mobile unit at a closer distance to a mobile unit at a longer distance to collect the iD code. On the other hand, when the iD code sending side outputs its own code signal, it does not respond for a certain period of time or until a certain calling circuit elapses, and the center side makes a series of iD code within that time or number of times.
Complete the code collection operation.

[Embodiment] FIG. 1 is a configuration diagram showing an embodiment of the present invention, and shows a configuration of a transponder 1 and a center side device 2 which are attached to a moving body (not shown). Responder 1 is antenna 11,1
4, a switch element 12, a power supply 13, a control circuit 15, a transmission output circuit 16, etc., the center side device 2 is a control circuit 2
1, the antennas 22 and 24, the reception data processing device 23, and the like. In addition, the transmitting antenna of the transmitter / receiver 22 is 1
Although one or more are provided, only one of them is shown here and the others are omitted.

A ringing signal source is provided in the control circuit 21, which gives an electromagnetic field change to the outside through the antenna 22 (possibly a loop coil). Therefore, when a moving body (not shown) approaches or enters the electromagnetic field change region, the ringing signal receiving antenna 11 (or coil in some cases) of the transponder 1 attached to the moving body causes the electromagnetic field change. Is converted to a voltage signal. When the voltage signal reaches a level at which the switch element 12 is activated (turned on), the power supply 13 is supplied to the control circuit 15 and the transmission output circuit 16 through the switch element 12 to activate the individual identification transmission function. The control circuit 15 to which the power supply 13 is supplied is
Is turned on until the end of transmission of the individual identification code,
The switch element 12 is operated so that the power source is held by itself. The control circuit 15 which has secured the power supply outputs the individual identification (iD) code preset here to the transmission output circuit 16. The transmission output circuit 16 is composed of an oscillation, modulation, and power conversion unit, modulates a carrier signal with a signal input from the control circuit 15, amplifies the power, and sends out from the transmission antenna 14 as an electromagnetic wave. The electromagnetic wave output from the transmitting antenna 14 is received by the receiving antenna 24 of the center side device 2. The received electromagnetic wave demodulates the iD code from the transponder 1 by the reception data processing device 23 and identifies it. In this way, the iD code from the mobile can be collected. It is assumed that the reception data processing device 23 includes, for example, a microcomputer and the like, and includes demodulation, amplification, shaping circuits, and the like.

However, if a plurality of mobile objects T ₁ , T ₂ , T ₃ exist within the radio wave area A of the antenna 22 as shown in FIG. As described above, the iD code cannot be collected because a plurality of mobile bodies simultaneously respond to the call signal of. However, at this point, it is understood that at least the iD code of T ₁ can be extracted by narrowing the transmission power of the antenna 22 and setting the directional characteristic to A '. For this the antenna
It is necessary to adjust the power of 22 and this adjustment is performed by the control circuit 21 of FIG. 1 or 2. However, while the power adjustment is gradually increased from small to large,
On the mobile side, it is necessary that once the iD code is transmitted, the iD code is not transmitted again for a certain period of time or until a certain number of times of calls have elapsed. This is because, for example, when the transmission radio wave is adjusted to the directivity that can cover the mobile unit T ₂ in FIG. ₂ , the mobile unit T ₁ also enters the area, and the iD code cannot be identified. This is a measure to avoid.

Further, since the response sensitivity changes depending on the angle between the ringing signal receiving antenna 11 and the ringing signal transmitting antenna 22, and the detection distance characteristics also usually vary depending on this angle, a plurality of antennas 22 are provided. It is desirable to place them. FIG. 3 (a) shows an example in which two antennas 22 and 22 'are arranged. In this case, the antennas 22 and 22 'are
When they are alternately driven as shown in (c) and (c), their transmission powers AT ₁ ...... AT ₆ , AT ₁ ′ ... AT ₆ ′ are also gradually increased over time. By doing this,
'A ₂ in FIG at (i), A _{2' 2} two antennas 22, 22, A _4,
It is possible to form a ringing signal area that changes sequentially like A ₄ ′, A ₆ , and A ₆ ′.

The response control as described above on the responder side to the transmission control by the center side device is performed by the control circuit 15. The control operation is shown by a time chart in the fourth example.
FIG. 5, FIG. 5 and FIG. That is, FIG. 4 shows an example in which the responder returns a response signal to the call signal from the center side device, and then does not send the iD code for a certain period of time. Is an example when iD code is not sent. Also, FIG.
This is an example in which the calling cycle is made faster than in the figure. In these figures, (a) is a calling signal S and (b) is a response signal R.
Indicates. Therefore, by performing such response control together with the transmission control on the center side, it becomes possible to collect the iD codes from a plurality of moving objects existing in a predetermined area separately from each other.

Although an example in which two antennas are installed in a direction orthogonal to each other has been described above, the number and arrangement of antennas can be adjusted according to the size of individuals, the number of individuals existing in a predetermined area, and the like. Further, the present invention can be widely used in general technical fields in which it is necessary to collect the above-mentioned iD codes.

〔The invention's effect〕

According to the present invention, the center side device is provided with an antenna for transmitting a calling signal, and the calling signal is sent while the amplitude is gradually increased over time, while the responder side iD
Every time the code signal is sent back to the center side device, the iD code is not sent again until a predetermined number of times or a certain number of ringing is reached, so even if there are multiple moving objects within the predetermined area, the iD code The advantage is that they can be taken out separately from one another.

[Brief description of drawings]

FIG. 1 is a configuration diagram showing an embodiment of the present invention, FIG. 2 is an explanatory diagram for explaining the relationship between the directivity of an antenna and a moving body, and FIG. 3 is a transmission device of the center side device in FIG. FIG. 4 is an explanatory view for explaining the antenna and its operation, FIG. 4 is a time chart showing an example of the adjusting operation in the transponder, and FIG.
FIG. 6 is a time chart showing another example of the adjusting operation in the responder, and FIG. 6 is a time chart showing yet another example of the adjusting operation in the responder. Code explanation 1 …… Responder, 11,14,22,22 ′, 24 …… Antenna, 12 ……
Switch element, 13 ... Power supply, 15, 21 ... Control circuit, 16 ...
… Transmission output circuit, 23 …… Reception data processing device.

Claims (2)

[Claims] 1. A center side device issues the ringing signal to a moving body having a responder that moves within a predetermined area and receives a ringing signal from the outside to return a unique identification (iD) code signal. In the iD code collecting method for collecting the iD code signal, the center side device is provided with a transmitting means for transmitting a calling signal, and control for sending the calling signal with the amplitude gradually increasing over time. On the other hand, in the responder, each time the iD code signal is returned to the center side device, the iD code signal is controlled not to be transmitted again for a predetermined time or until a certain number of ringing is reached. The iD code collection method characterized in that the iD code is separated from the moving body and taken out. 2. The iD code collecting method according to claim 1, wherein a plurality of the transmitting means are provided so as to transmit the calling signals in mutually different directions, and the calling signals of the transmitting means are mutually predetermined for a predetermined time. An iD code collection method characterized in that each transmission means is controlled so that they are transmitted in a time-division manner.